Segments and Related Information (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014 segment	Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Segment reporting, factors used to identify entity's reportable segments	MasTec presents its continuing operations in five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial and (5) Other. This structure is generally focused on broad end-user markets for MasTec's labor-based construction services.
Number of reportable segments	5
Segment reporting information, description of products and services	All five reportable segments derive their revenues from the engineering, installation and maintenance of infrastructure, primarily in North America.
Segment reporting, description of all other segments	The Other segment primarily includes small business units that perform construction services for a variety of end markets in Mexico and elsewhere internationally.
Revenue	$ 964,029,000	$ 918,648,000
Property and equipment, net	509,585,000		488,132,000
Intangible assets and goodwill, net	1,084,500,000		1,066,100,000
United States [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Revenue	837,900,000	878,900,000
Property and equipment, net	461,800,000		436,900,000
Intangible assets and goodwill, net	995,800,000		973,300,000
Foreign Operations [Member] | Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Revenue	126,100,000	39,700,000
Property and equipment, net	47,800,000		51,200,000
Intangible assets and goodwill, net	88,600,000		92,700,000
Communications [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services	The Communications segment performs engineering, construction and maintenance of communications infrastructure primarily related to wireless and wireline communications and install to the home, and to a lesser extent, infrastructure for electrical utilities.
Communications [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	447,100,000	424,900,000
Communications [Member] | Customer Concentration Risk [Member] | Revenue [Member] | Utilities [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Utilities customers, percentage of consolidated communications revenue	7.00%	8.30%
Oil and Gas [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services	MasTec performs engineering, construction and maintenance services on oil and natural gas pipelines and processing facilities for the energy and utilities industries through its Oil and Gas segment.
Oil and Gas [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	379,800,000	318,800,000
Electrical Transmission [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services	The Electrical Transmission segment primarily serves the energy and utility industries through the engineering, construction and maintenance of electrical transmission lines and substations.
Electrical Transmission [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	80,100,000	84,600,000
Power Generation and Industrial [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services	The Power Generation and Industrial segment primarily serves the energy and utility end markets and other end markets through the installation and construction of renewable power facilities, related electrical transmission infrastructure, ethanol facilities and various types of industrial infrastructure.
Power Generation and Industrial [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	$ 54,200,000	$ 88,900,000